Wednesday, April 21, 2010

The TBM Cutterhead Arrives

The cutterhead for the Tunnel Boring Machine
has arrived at the launch box.

This piece will be mounted later tonight onto the cutterhead support (the piece that arrived last night) and before long S3 Tunnel Constructors (the contractor for this part of the project) will be ready to start the first tunnel drive towards 63rd Street.

In case you're wondering, the tunneling is currently scheduled to start in mid-May, after a shakedown period for the machine.

As background - the machine on this project is a Robbins Main Beam Tunnel Boring Machine. It is now being assembled inside the so-called TBM launch box under Second Avenue, between 92nd and 95th streets. The launch box has been under construction for just over 3 years now.

All of the ground level shots, unless noted otherwise, were taken from the west side of Second Avenue, between 91st and 92nd streets.

The aerial shots were taken from an apartment on the NW corner of The Waterford, a residential building located at 300 East 93rd Street.

Note that you can left-click on any image to view it in a high-definition format.

East 92nd Street - looking N
9:25 p.m. EDT

The rig with the cutterhead rolled into town just before 9:30 p.m. -- just as I was walking over to work site to capture a set of images for the blog.

9:26 p.m.

The truck has just come to a stop and the men are now working to remove the chains that were used to secure the cutterhead to the trailer.

Take a close look at the 10-axle platform trailer that they used to transport this thing.

It [the trailer] was made in Europe somewhere (probably France) by the company Nicolas Industries. It's top speed is 60 km/hr (approx 36 m.p.h.) according to the sticker that I noticed on the rear of the trailer. (I wonder what the toll was to get it across the GW?)

9:35 p.m.

In this image workers can be seen connecting the slings (which are green) to the 123,000 pound (61 1/2 ton) cutterhead so that it can be lifted off the trailer.

9:37 p.m.
Courtesy of JSL

9:39 p.m.

In this shot you can clearly see the backside of the cutterhead. This surface will be mated up against the surface of the cutterhead support that was lowered into the hole last night.

9:51 p.m.

This is a close-up shot of part of the cutterhead. When you look closely at it you can see that the actual disk cutters have not yet been mounted.

I was told that the letter "Q" was painted on it on purpose - since this TBM will be digging the tunnels for the extension of the Q Line.

See if you can figure out why the cutterhead has been painted yellow. (you'll find the answer at the end of this posting.)

9:52 p.m.

Now the crane very carefully lifts the piece into a vertical position.

9:53 p.m.

9:54 p.m.

At the moment I can't figure out what in the world "ADI" stands for. If anyone has any ideas please post a comment or drop me an e-mail.

9:55 p.m.
Courtesy of JSL

9:55 p.m.

Now the crane slowly moves the piece towards the hole, as workers on two sides steady it using ropes.

9:56 p.m.
Courtesy of JSL

9:56 p.m.

The cutterhead is now positioned over the hole.

9:57 p.m.
Courtesy of JSL

near the SE corner of East 92nd & 2nd - looking W
9:59 p.m.

10:00 p.m.
Courtesy of JSL

near the SE corner of East 92nd & 2nd - looking W
10:00 p.m.

And at 10 p.m. the cutterhead dropped below street level.

And that was it.


Now for the answer to the question, "why did they paint the cutterhead yellow?"

Answer: Because that's the color that the MTA uses to designate the Q Line on route signs, station signs and the official subway map.


Related links:

A Doughnut on 2nd Avenue - April 20, 2010
The Launch Box

The Main Beam - April 19, 2010
The Launch Box